This invention refers to a safety device intended to prevent the unauthorized use of a fire-arm of the kind whose barrel has at least one recess in at least one location of its inner surface. At least one recess is present in most of the modern fire-arm barrels.
The potential danger represented by fire-arms which can be improperly used by unauthorized persons has suggested to provide safety devices having a lock, which can be mounted onto the fire-arm in such a manner as to prevent the operation thereof until the safety device has been removed by a person provided with the proper key corresponding to the lock of the safety device.
On the basis of this principle, there have been proposed some safety devices which can be mounted in the region of the trigger of the fire-arm in such a way as to prevent its operation. However these safety devices have not been deemed satisfactory, mainly in that they can easily be inoperative when imperfectly mounted. Moreover, the thus protected fire-arm can still be operated by using sagacious contrivances. Finally, these safety devices cannot surely prevent the shot of a projectile which was already in shot position within the barrel when the safety device has been mounted onto the fire-arm. In effect nothing prevents such a safety device to be installed, voluntarily or by inadvertence, on a fire-arm whose projectile is in the shot position.
There has also been proposed a safety device which comprises a false cartridge-case extended by a steel cable which can receive the application of a padlock. The false cartridge-case is inserted into the barrel of the fire-arm from the rearward end thereof, with the steel cable extending along the barrel and projecting from the forward end thereof, and this cable is then blocked by means of the padlock. Such a device ensures a complete safety, but it has the heavy drawback that, when the fire-arm should be put again in condition of use, a complicated maneuver and a noticeable delay are needed for removing the false cartridge-case after opening of the padlock. This can jeopardize a timely intervention by the use of the fire-arm in urgent cases.
There have also been proposed safety devices in which a shaft introduced into the barrel of a fire-arm is provided of some members which can be made to expand against the inner surface of the barrel, and then blocked by means of a lock in this expanded position. The thus expanded members normally prevent removing the shaft from the barrel, but they act only by friction, whereby the application of a force strong enough allows to violate the safety device. Moreover, the mechanisms of such safety devices are excessively complicated and weak.
Finally, there have been proposed safety devices intended to prevent the unauthorized use of a fire-arm of the kind whose barrel has a recess in a location of its inner surface; more precisely, such devices are destined to be mounted onto a revolver. These safety devices include a body intended to be inserted into the fire-arm barrel and provided with a rotatable latch eccentrically mounted on the rear end portion of the body. The rotatable latch is suitable for keeping an inactive position, in which it does not project out of the periphery of the body and therefore it does not hinder the insertion of the body into the fire-arm barrel, and an active position in which a portion of the latch a projects with respect to the periphery of the body and engages the recess of the fire-arm barrel, thus blocking the body relative to the fire-arm barrel. A transmission member is connected to the rotatable latch and to a lock mounted within the forward end portion of the body, this lock being operable by means of a proper key in order to rotate the latch through the transmission member between its inactive and active positions.
Such a safety device cannot be installed when a projectile is in the shot position, whereby, if such projectile is present, it should be removed in order that the safety device can be installed. After the device is installed with the latch in inactive position, by operating the lock and removing its key the latch is rotated in its active position, it engages the recess of the fire-arm barrel and prevents the removal of the safety device until the latch has been moved again to its inactive position by operating the lock by means of the proper key.
In theory, this known safety device solves the safety problem, and in some applications, such as with revolvers, it is satisfactory also in the practice, but it is not effective in other applications. In several cases, and mainly in the automatic pistols, unlike the revolvers, the recess present in the fire-arm barrel has a very limited depth, whereby it is not possible to ensure an effective engagement of the latch by keeping into account the different tolerances of manufacture, the clearance needed for inserting the device body into the fire-arm barrel and also, in certain cases, the conicity of the barrel mouth, foreseen in order to facilitate the entrance therein of the cartridge. Even when the engagement is attained, it is somewhat failing because, under a force strong enough, some parts can be disformed and then allow removing the safety device.
In view of the foregoing, the main object of the present invention is to provide a safety device with a lock, intended to be applied to a fire-arm of the kind whose barrel has at least one recess in at least one location of its inner surface, in order to prevent its unauthorized use, which device should offer a complete safety even against strong actions, and which should require only a very simple, quick and easy maneuver for putting the fire-arm in condition of use by a person which has the proper key corresponding to the device lock.
Another object of the invention is to provide such a safety device which cannot be incorrectly mounted so as to elude its function.
Still another object of the invention is to provide such a safety device which can be industrially manufactured in a convenient way and at a reasonable cost.
The safety device of the invention is of the kind which comprises a device body intended to be inserted into the barrel of a fire-arm and having a rotatable latch eccentrically mounted at the rear end portion of the device body and suitable for keeping an inactive position, in which it does not project out of the periphery of the body and therefore does not hinder the insertion of the device body into the fire-arm barrel, and an active position in which a portion of the latch projects with respect to the periphery of the device body and engages a recess of the fire-arm barrel, thus blocking the device body relative to the fire-arm barrel, and a transmission member connected to the rotatable latch and to a lock mounted within the forward end portion of the device body, this lock being operable by means of a proper key in order to rotate the latch through the transmission member.
According to the invention, a safety device of this kind further comprises a slider, guided by the device body in order to be displaceable along a diametrical direction with respect to the device axis, and to the rotatable latch is coupled in rotation a cam engaging said slider in order to displace the same, by action of the rotation of said transmission member, between an inactive position, in which the slider is included within the periphery of the device body, and an active position, in which a portion of the slider projects out of the device body at the side opposite the side wherein, in its active position, projects a portion of the rotatable latch, both the rotatable latch and the slider being thus moved to their respective active or inactive positions by the same rotation of the transmission member.
Within the frame of this main feature, the parts of the safety device can be designed in different manners.
In a first manner, the diametrically displaceable slider is intended to engage, in its active position, a recess of the fire-arm barrel, whilst the rotatable latch rests, in its active position, against the opposite wall of the barrel.
In a second manner, the rotatable latch is intended to engage, in its active position, a recess of the fire-arm barrel, whilst the displaceable slider rests, in its active position, against the opposite wall of the barrel.
In a third manner, both the rotatable latch and the diametrically displaceable slider are intended to engage, in their respective active positions, each a recess of the fire-arm barrel.
Thanks to these features, the presence of two members which, in the active condition of the safety device, project from opposite sides of the device body, allows in any case to compensate for any clearance, irrespective of its origin, and excludes that the disformation under stress of some parts could allow the unauthorized removal of the safety device by suppressing the engagement of a projecting member with a recess of the fire-arm barrel. The safety device is thus able to withstand even very strong violation actions. On the other hand, the mechanisms used are of a great simplicity, and therefore the safety device is relatively inexpensive and very reliable.
Preferably, the device body comprises an outer skirt so shaped as to positively engage the outer end portion of the fire-arm in order to render the device body positively solid with the fire-arm when inserted thereon.
As it may be remarked, the invention can be applied only to fire-arms whose barrel has at least one recess in its inner surface, however this fact does not heavily limit the application of the invention, because that circumstances are verified in about all the modern fire-arms. The invention may find application in any kind of fire-arms, however its typical application is to the automatic pistols. For this reason, the following description will refer to said specific application.